Conjunctival infection with Chlamydia trachomatis in sexual partners of patients with adult inclusion conjunctivitis

Development and validation of a health practitioner survey on ocular allergy

Survey studies have played a significant role in understanding the gaps in the knowledge and practices of health practitioners. However, there have been no such survey studies on Ocular Allergy (OA). Thus, the purpose of this study was to develop and validate a survey on OA to better understand the gaps in the diagnostic, treatment, and collaborative care approaches of health practitioners in OA. The survey is titled "Survey on Ocular Allergy for Health Practitioners (SOAHP)". SOAHP was developed in a five-stage process. First, item extraction via the use of a literature review, second, face and content validity, third, a pilot study, fourth, test-retest reliability, and fifth, finalisation of the survey. 65 items under 6 domains were initially generated in the item extraction phase. Content validity was conducted on 15 experts in the field. This was conducted twice to reach consensus whereby items and domains were added, edited, kept, or removed, resulting in 50 items under 7 domains. The pilot study was conducted on 15 participants from the five relevant health practitioner fields (Allergists/Immunologists, General Practitioners (GPs), Ophthalmologists, Optometrists and Pharmacists). This altered the survey further to 40 items under 7 domains. Test-retest reliability was conducted on 25 participants from the five health practitioner fields. Reliability was moderate to almost perfect for most (97%) investigated items. The finalised survey was 40 items under 7 domains. SOAHP is the first survey created to assess diagnostic, treatment and collaborative care approaches of Allergists/Immunologists, GPs, Ophthalmologists, Optometrists and Pharmacists on OA. SOAHP will be a useful tool in clinical research on OA.

Refinement of water-filtered infrared A (wIRA) irradiations of in vitro acute and persistent chlamydial infections

Water-filtered infrared A (wIRA) alone or in combination with visible light (VIS) exerts anti-chlamydial effects in vitro and in vivo in acute infection models. However, it has remained unclear whether reduced irradiation duration and irradiance would still maintain anti-chlamydial efficacy. Furthermore, efficacy of this non-chemical treatment option against persistent (chronic) chlamydial infections has not been investigated to date. To address this knowledge gap, we evaluated 1) irradiation durations of 5, 15 or 30 min in genital and ocular Chlamydia trachomatis acute infection models, 2) irradiances of 100, 150 or 200 mW/cm² in the acute genital infection model and 3) anti-chlamydial activity of wIRA and VIS against C. trachomatis serovar B and E with amoxicillin (AMX)- or interferon γ (IFN-γ)-induced persistence. Reduction of irradiation duration reduced anti-chlamydial efficacy. Irradiances of 150 to 200 mW/cm², but not 100 mW/cm², induced anti-chlamydial effects. For persistent infections, wIRA and VIS irradiation showed robust anti-chlamydial activity independent of the infection status (persistent or recovering), persistence inducer (AMX or IFN-γ) or chlamydial strain (serovar B or E). This study clarifies the requirement of 30 min irradiation duration and 150 mW/cm² irradiance to induce significant anti-chlamydial effects in vitro, supports the use of irradiation in the wIRA and VIS spectrum as a promising non-chemical treatment for chlamydial infections and provides important information for follow-up in vivo studies. Notably, wIRA and VIS exert anti-chlamydial effects on persistent chlamydiae which are known to be refractory to antibiotic treatment.

Maraviroc, celastrol and azelastine alter Chlamydia trachomatis development in HeLa cells

Introduction . Chlamydia trachomatis (Ct) is an obligate intracellular bacterium, causing a range of diseases in humans. Interactions between chlamydiae and antibiotics have been extensively studied in the past.Hypothesis/Gap statement: Chlamydial interactions with non-antibiotic drugs have received less attention and warrant further investigations. We hypothesized that selected cytokine inhibitors would alter Ct growth characteristics in HeLa cells.Aim. To investigate potential interactions between selected cytokine inhibitors and Ct development in vitro.Methodology. The CCR5 receptor antagonist maraviroc (Mara; clinically used as HIV treatment), the triterpenoid celastrol (Cel; used in traditional Chinese medicine) and the histamine H1 receptor antagonist azelastine (Az; clinically used to treat allergic rhinitis and conjunctivitis) were used in a genital in vitro model of Ct serovar E infecting human adenocarcinoma cells (HeLa).Results. Initial analyses revealed no cytotoxicity of Mara up to 20 µM, Cel up to 1 µM and Az up to 20 µM. Mara exposure (1, 5, 10 and 20 µM) elicited a reduction of chlamydial inclusion numbers, while 10 µM reduced chlamydial infectivity. Cel 1 µM, as well as 10 and 20 µM Az, reduced chlamydial inclusion size, number and infectivity. Morphological immunofluorescence and ultrastructural analysis indicated that exposure to 20 µM Az disrupted chlamydial inclusion structure. Immunofluorescence evaluation of Cel-incubated inclusions showed reduced inclusion sizes whilst Mara incubation had no effect on inclusion morphology. Recovery assays demonstrated incomplete recovery of chlamydial infectivity and formation of structures resembling typical chlamydial inclusions upon Az removal.Conclusion. These observations indicate that distinct mechanisms might be involved in potential interactions of the drugs evaluated herein and highlight the need for continued investigation of the interaction of commonly used drugs with Chlamydia and its host.

Chlamydia Conjunctivitis in 2 Prepubertal Children: An Uncommon Presentation of Child Sexual Abuse

Sexually transmitted infection as the result of child sexual abuse in prepubertal children is uncommon. Chlamydia trachomatis conjunctivitis is an even less common entity in prepubertal children outside the newborn period. This report details the presentation of 2 children with conjunctivitis who were subsequently diagnosed as having C. trachomatis conjunctivitis. One child was also diagnosed as having rectal and pharyngeal C. trachomatis infection, and the other also had genital C. trachomatis infection. Even with multisite C. trachomatis infection as an indication of sexual abuse, neither child gave a detailed disclosure of abuse to account for their infections. The absence of a clear disclosure is not uncommon. Previous literature reports that a disclosure in these circumstances occurs in less than half of cases. In this report, we review the recommendations for diagnosis of C. trachomatis using nucleic acid amplification testing and culture as well as treatment. Specific clinical features should alert the clinician to C. trachomatis conjunctivitis and lead to timely diagnosis and protection of the child from further sexual abuse.

Low Prevalence of Conjunctival Infection with Chlamydia trachomatis in a Treatment-Naïve Trachoma-Endemic Region of the Solomon Islands

BACKGROUND

Trachoma is endemic in several Pacific Island states. Recent surveys across the Solomon Islands indicated that whilst trachomatous inflammation-follicular (TF) was present at levels warranting intervention, the prevalence of trachomatous trichiasis (TT) was low. We set out to determine the relationship between chlamydial infection and trachoma in this population.

METHODS

We conducted a population-based trachoma prevalence survey of 3674 individuals from two Solomon Islands provinces. Participants were examined for clinical signs of trachoma. Conjunctival swabs were collected from all children aged 1-9 years. We tested swabs for Chlamydia trachomatis (Ct) DNA using droplet digital PCR. Chlamydial DNA from positive swabs was enriched and sequenced for use in phylogenetic analysis.

RESULTS

We observed a moderate prevalence of TF in children aged 1-9 years (n = 296/1135, 26.1%) but low prevalence of trachomatous inflammation-intense (TI) (n = 2/1135, 0.2%) and current Ct infection (n = 13/1002, 1.3%) in children aged 1-9 years, and TT in those aged 15+ years (n = 2/2061, 0.1%). Ten of 13 (76.9%) cases of infection were in persons with TF or TI (p = 0.0005). Sequence analysis of the Ct-positive samples yielded 5/13 (38%) complete (>95% coverage of reference) genome sequences, and 8/13 complete plasmid sequences. Complete sequences all aligned most closely to ocular serovar reference strains.

DISCUSSION

The low prevalence of TT, TI and Ct infection that we observed are incongruent with the high proportion of children exhibiting signs of TF. TF is present at levels that apparently warrant intervention, but the scarcity of other signs of trachoma indicates the phenotype is mild and may not pose a significant public health threat. Our data suggest that, whilst conjunctival Ct infection appears to be present in the region, it is present at levels that are unlikely to be the dominant driving force for TF in the population. This could be one reason for the low prevalence of TT observed during the study.